Truth Tuesday: January 26, 2010

cont. from 1/19/2010

Revving and (Sorta) Willing 6:35 a.m.

The starting gun goes off in 10 minutes. Even though prerace jitters make me want to hurl, I suck down an energy gel, sip some water, and wade into the lake for a quick warmup. What's going onThe blood can hold about 100 calories' worth of easy-to-access glycogen, and I want my tank at full capacity. Eating a simple carb, like a banana or an energy gel, within 30 minutes of a tough workout tops it off.

As for that pukey feeling: Anticipation has my heart beating fast--my nervous system is primed for action. "It's like waving a leash in front of a dog," says Matt Fitzgerald, author of Brain Training for Runners. "The dog knows it's going for a walk and gets excited." A 10-minute warmup gets blood flowing to my muscles and away from other organs, revs my heart rate, starts working my lungs, lubes my joints, and reacquaints my nervous system with how my muscles fire. In a race, skipping a warmup means a breathless, achy start.

Knowledge is power

To make a tough workout seem easier before you even start, "break it into manageable parts: Warm up, then set an easy goal: five minutes, one mile, or something similarly doable," says Abby Ruby, Ph.D., a senior coach at Carmichael Training Systems in Colorado Springs. "Don't worry about minute 45 at minute 10."

High Gear 6:45 a.m.

The starting gun fires. I dive in for the 1,500-meter swim. Breathing is a struggle, and my arms and legs protest. What's going onAs picky as a diesel-powered Jetta, my body runs on only one fuel: ATP. At the beginning of a hard effort, the body makes this muscle food using creatine, an acid it produces naturally. "This ATP is created in a flash," Katz says, "and is gone just as quickly." At the start of a workout, my cells have just under 10 seconds' worth of this fuel. Then a process called anaerobic glycolysis kicks in. For the next one to three minutes, I can produce ATP without oxygen (right now I'm using all I've got to breathe).

The trade-off: I cringe as my muscles start to burn. Now my system switches to the lowest-maintenance way of making ATP: aerobic glycolysis. Here, a combo of oxygen, glycogen (from my breakfast and last night's linguine), lactic acid, and fat stores feed my muscles. The body can run this way for hours; in fact, it uses this form of ATP for 99 percent of all activity. Meanwhile, my adrenal glands release epinephrine (aka adrenaline), raising my heart rate and lowering my perception of pain. "Epinephrine is the cavalry swooping in for a fight, which is how your body sees this race," says Tommy Boone, Ph.D., an exercise physiologist at the College of St. Scholastica in Duluth, Minnesota. My nervous system doesn't know if I'm being chased by competitors or a great white shark. Either way, its message is the same: Go fast and hard.